I am pretty much clueless, in general; however, I might report that I, too, recently experienced this same breakdown in all of the net interfaces on one of my machines. This appeared after a massive update to a ~x86 system involving over 700MB of downloads. It took several days to perform the update, and --- albeit I cannot pinpoint the exact cause of my griefs (X11 also failed when started from the enlightenment display manager 'entrance') after I had finally gotten my network connection established and run all of the following, everything works again.
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